[Investigation and analysis of the bacteria community in silkworm intestine]

Majority of the environmental microorganisms are still unculturable. To shed a light on the bacteria community in the silkworm intestine more completely, culture-dependent and culture-independent methods were used to perform the investigation. As the latter, 16s rRNA gene was amplified and a library was constructed by using the meta-genomic DNA extracted from the bacteria in the silkworm intestine as template. Restriction fragment length polymorphism (RFLP) method was used to screen recombinants originated from different bacteria, and the nucleotide sequences were determined. A BLAST searching in the GenBank and an analysis on phylogenesis were performed. The taxonomy of these bacteria and their physiological function to silkworm were speculated. Results showed that the bacteria in silkworm intestine are mainly belong to the genera Arthrobacter, Lactobacillus, Pseudomonas, Escherichia, Micrococcus, Bacillus, and Staphylococcus. They may play important roles to the host silkworm in the utilization of their food mulberry and disease prevention. Both the culture-dependent and culture-independent methods have their advantages and disadvantages, and they are complemented with each other.